This application proposes to establish an interdisciplinary and international research team and agenda and strategy for improving understanding about the role of sexual violence and genito- anal injury in HIV transmission, acquisition and pathogenesis. Funding is sought for a series of three scientific meetings to advance the scientific research priorities emerging from the Greentree Scientific Research Planning Meeting on Sexual Violence, Genito-anal Injury and HIV Transmission. This unique interdisciplinary gathering, convened by the SSRC with support from UNAIDS and the NIH, identified physiological and social co-factors of sexual violence that are understudied but potentially significant for understanding epidemic's disproportionate geographic and gender distribution. The meetings will provide an opportunity to develop an interdisciplinary research team and agenda with a shared conceptual and methodological framework that can overcome the disciplinary-specific approaches that have been unsuccessful in tackling an inherently bio- social problem. The process will result in a workable research plan for carrying out the exploratory and developmental research needed to address the methodological and feasibility questions arising during the planning process. The aim is to identify the most critical areas of needed data collection that are likely to have a significant impact on the field and begin to signa directions for prioritizing interventions. The plan will also seek to inform the USG National Strategy to Prevent and Respond to Gender Based Violence, adopted in August2012, and PEPFAR's GBV strategy which seeks to close gaps in countries where systematic gender-based violence prevalence data has not been collected/ Increased understanding about the relative contribution of genito-anal injury to important predictive variables such a 'risk behavior and 'modes of exposure' and 'high and low risk heterosexual transmission' will improve understanding about the social drivers that influence unprotected heterosexual vaginal and anal sex. Increased understanding about the distribution of HIV among sub-populations that are at highest risk of sexual violence will improve the design and prioritizing of combination prevention interventions that are most likely to reduce the risk of sexual violence and its potential contribution to HIV transmission.